What did you mod today?

I did a test here but I didn’t test for a very long duration.

that makes sense…

apparently the CRI test does not show that reduction, it seems to rescale all the bars higher, not lower

that does not mean the comment is wrong, to me it means the CRI test is faulty. Because the test makes the filter look good on paper, but not in my reality.

from my personal experience with Lee minus green filters, they make the illuminated area Look like there is a Pink wash over everything … I really dont care for them, at all. They are, to me, just a cheap plastic toy to play with… I do not take them seriously, and would not want one on a light I consider valuable or special…

and yes, the lumen penalty is another reason I lose interest in filters…

They degrade over time.

Regular Lee filters degrade very fast. A few months at most in a high output light.

Lee Zircon filters are specially designed for LED use. They last much longer. They’ll still degrade, but I suspect it might be a few years before it is really noticeable.

Fortunately, the filters come in sheets. One sheet gives enough material for many filters.

The “pink wash” you mention is probably just the filter lowering the color temperature lowering to something below what you prefer.

If you prefer 4500K, you probably won’t be happy putting a filter on your 4500K LED. The filter might lower the color temperature below 4000K. Try starting with an LED with a cooler color temperature than you normally use. Then when you apply the filter, hopefully it will lower the color temperature to your preferred level.

Also, if things look TOO pink, the issue might be the filter lowered the output too far below the Black Body Line. In that case, perhaps the minus green filter you’re using is too strong. Try a weaker filter that does not remove as much green.

My main EDC is an FW1A that I installed an LH351D @ 4000k into as soon as I bought it. I would love to try this out for grins, how small a chunk can the Zircon filters be purchase in and do you just cut them with scissors?

Thanks Matt

Yes cut with scissors

Small sheets from boaz

Full sized sheets

this swatch book has a 1x3” piece of over 200 samples… among them are about 5 levels of minus green

they are not the high temperature Zircon version… I think Boaz is better for that

imo, you would do better by slicing the domes, than putting pink plastic (lee filters) under the lens… yes, its thin plastic, and cuts easily… I use the lens as a template and cut around with an exacto… I cant cut a round circle with scissors at all.

Jon, I am not unhappy with the color temperature… but the led does not seem to have the pop I expected. It just does not seem to live up to the CRI numbers. I chose that emitter due to the fact that it is the right temperature, pretty efficient and works really well in the reflector. The SST-20 had a to tight hotspot along with an XP-L Hi and the HD just does do anything for me. I have never tried to change the tint in this manner. I do use them from time to time with digital IR photography, but that is a different beast.

I also find the LH351d a bit “washed out”.
I blame two factors that are different than the SW45k
The LH351d has less R9 CRI (specifically the Red output). The SST and sw45k are 90+ R9 CRI… the LH351d is lucky to hit 70…

the second factor is that LH351d, and also SST-20, have positive DUV, iow, Tint above the BBL, in the yellow/green range, instead of the sw45k which has tint below BBL

by slicing the LH351d, you move the Tint below the BBL… it does also lower the CCT 500 points

anyway, I hope you find a combination that suits you.

I agree btw that both the SST and 219b have smaller hotspots than the LH351d…

the supposed extra efficiency of the LH351d is spread over a larger target, so though more total lumens, is not necessarily more Lux on target

the LH351d tried to lay a claim to the sw45k throne, and imo, the coup failed miserably

even after cutting the dome off the LED… LOL

I quite like sliced LH351D. Specifically the “dog farts” bin at 5000K.

Output feels a lot like XPL HI, but with better CRI.

Yes, with most other high CRI / low R9 emitters I’ve tested the filter with I usually get R9 coming in around the 70s. The Zircon filters do seem to be particularly suited to the LH351D’s phosphor mix.

I don’t notice any diffusion of the beam. It’s slightly less intense due to slight loss of lumens (in this case about 15% flux) but the hotspot is the same size.

The output is being slightly lowered but the test isn’t faulty. A spectrometer compares a number of color samples to a set of known samples under a 100 CRI (incandescent) source and figures the difference. More deviation results in a lower R (x) number. If the spectrometer is reading the R (x) value as high, in this case it means the filter is causing the color to be rendered very closely to how it appeared under a 100 CRI source (with all other considerations such as CCT and tint taken into account).

If your filter caused the light to become washed in a pink hue, you probably used a much too aggressive filter and went too negative on the Duv. I personally find an LED that is too pink to be just as offensive as a green one.

Slicing the dome of the LH351D does improve the tint slightly but not to the same degree as a filter. It will also result in a much more aggressive shift in color temperature. You will also lose some luminous flux, just as with a filter (though slicing will result in an increase in intensity).

Also keep in mind that while slicing the LH351D results in a decrease in Duv, this won’t be the case with all LEDs. With most emitters, Duv will increase significantly after sliced or dedomed.

I agree, did not notice much diffusion, just coloration…

Very helpful. Thanks for helping me to understand better… all the colors are being reduced by the filter, but at that reduced level, they are more balanced (R9 goes up and the others appear to also increase)


thanks, I did not know, was only addressing mattlward’s LH351d “low pop LH351d” solutions

you have convinced me mattlward should try a filter

I volunteer someone (Rayoui?) to sent mattlward a piece of Zircon 803 :wink:

I’d be willing to donate a piece of 803. I can also spare a piece of 802 and 804, for science.

:beer: :+1: :person_with_crown:

It would be interesting if the effects of each were tested.

I have an FW3A setup with sliced 351d’s, the dogfights. It is very nice indeed.

Regards Xandre

Here is a great post by maukka comparing several Zircon filters and some standard minus green filters.

Hi Xandre,
How do you keep the fresnel lens flat? It is really big but still thin plastic. Is it mounted all around in a stress-free way?

And what is the parabolic part of the body made of?

Lumintop TiTool AAA mod to 219b 3500k

Thanks for the link Rayoui - very interesting read.